1. Technical Field
The present invention relates to plywood flooring, and more specifically to plywood flooring, of which the plywood is heat-compressive treated and click-shaped in order to provide flooring materials having both of the advantages of reinforced floorboards and the advantages of plywood floorboards.
2. Background Art
For a dimensional stability of flooring material, plywood flooring is relatively better than reinforced floorboard, and for a construction velocity, the reinforced floorboard is excellent.
The detailed reasons are that the plywood is excellent for the dimensional stability, and a click fastening method (reinforced floorboard) makes the construction velocity to be done more quickly as compared to the use of rubber hammer (plywood flooring).
Japanese Patent Publication No. 2002-194885 discloses that plywood flooring material, in which various wood layers are laminated and each wood layer is adhered at the same time, includes a body part, a real part that is projecting out on at least one side of the body part, a bottom of groove part for inserting a real part of other plywood flooring material to the other side of the body part, and a groove part for reinforcement type on opposite side that is formed on the end between the side of the body part and the real part toward the body part. However, the real part and the groove part have T&G (Tongue and Groove) bonding structure.
Korean Patent Registration No. 674210 discloses a flooring board material for floor finishing composed of an end inserting part having an end downward projection that is projected downward on the bottom side and is projected to the outside on the end side, an end receiving part having an end downward groove that is formed inside from the center part of other end side and is embayed downward on the bottom side and makes a pair with an end inserting part, and a hot melt adhesive that is adhered on the other side, in which the flooring board material further includes a side inserting part having a lateral projection that is formed on one side end and a side downward projection that is projecting to the downward on the bottom side to be not continuous with the lateral projection, a side receiving part that is formed to the downward in a circular type on the inside of the side receiving groove that is formed on the other side end and has a side downward groove that is extended on the one point to the upward, and an end upward projection that is extended to the outside from the end downward groove and then projected to the upward, and also has about 30° of a fixed guided angle on the one side.
Korean Utility Model Registration No. 359803 discloses an adjustable flooring material, in which a projecting part is formed in a fixed length on two sides of one side, an inserting groove having a fixed depth is matched up with the projecting part on the other two sides, a groove has a role in passing air and is formed on the down center to prevent itself modification, an elastic material having a fixed thickness is adhered to the bottom of woodblock to buffer an impact and load applied from the up part of woodblock, a space part having a fixed size is formed on the bottom of the elastic material so that the inserting groove part of the woodblock is smaller than the woodblock, the projecting part of woodblock supports the bonding region of the projecting part and the inserting groove when bonding a plurality of woodblocks, the plywood material is adhered to be larger than the woodblock so that the bonding region is formed to be bound with the elastic material of the other flooring material that is assembled with the above flooring material, a plurality of fixed nails are inserted for bonding the wood material, the elastic material, and the plywood material on the bottom of the plywood material, and the projecting part and the inserting groove has T&G bonding structure.
Korean Utility Model Registration No. 399316 discloses a floor that is laminated with a natural marked type wood on the upper side of a composite panel of plastic fiber and wood fiber as a substrate. In the case of the above model, the key purpose is to provide the floor having a strength surface property that is a disadvantage of the plywood flooring, in which the floor can freely modify the appearance effect and the texture of the surface design, and the dimensional stability of the floor is the same level with the plywood flooring.
When the click structure is provided to the flooring material, it is easy to install the flooring material into the floor. Therefore, many researches are being performed to provide the click structure to a substrate, such as a wood, plywood, high density fiber board (HDF), and the like at home and aboard for a long time.
The click is easily provided to a substrate, such as HDF and a wood, but cannot be easily provided to the plywood. The reasons are that a density of the plywood (0.4˜0.6 g/cm3) is relatively lower than that of HDF (0.8 g/cm3) and a wood so that when providing the click to the plywood, the click shape will be broken or the processing surface of the click will be not smooth. For this reason, there are no the commercialized products, in which the click are given to the plywood within the country.
In addition, the existed plywood flooring may generate formaldehyde after constructing so that the problem about an indoor air quality exists. The reason is that a synthetic resin used for preparing plywood and an adhesive agent used for constructing the plywood flooring mainly causes the above problem.